JP3090547B2 - Collision type supersonic jet crusher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision type supersonic jet pulverizer using a high pressure gas as a jet stream.
More specifically, the present invention relates to a collision-type supersonic jet pulverizer for pulverizing an object to be pulverized into coarse particles.

[0002]

2. Description of the Related Art In order to obtain microscopic particles in the order of microns, especially fine particles having thermoplasticity such as thermoplastic resin powder and toner, coarsely crushed coarse particles are finely crushed using a collision type supersonic jet crusher. Things are going on. This collision type supersonic jet pulverizer is disclosed in, for example, Japanese Utility Model Laid-Open Nos. 51-100374 and 51-100375.
No. 740, JP-A-2-68155, and JP-A-3-195.
No. 43, for example.

[0003] The outline of the collision type supersonic jet crusher is as follows.
For example, as shown in FIG. FIG.
0, JP-A-2-68155, and JP-A-3-19543.
The main part substantially corresponds to the pulverizing device described in each publication. In FIG. 5, a material Ta to be crushed, such as a coarsely crushed resin, is charged from a raw material charging side indicated by reference numeral 1, and is guided to a classification process chamber 3 through a passage 2.
The crushed material Ta that has exited the classification process chamber 3 travels through the passage 4 to the jet jet flow path 5.

On the other hand, high-pressure air is jetted from the nozzle 6 by the inflow of the compressed air, and a supersonic jet flow is generated in the jet jet flow path 5 by air. A collision plate 7 is provided to oppose the jet flow direction.
The material to be crushed coming out of the supply port 5a is guided to a jet flow, rides on the jet flow, collides with the collision plate 7 while flying at a high speed (supersonic), and is crushed.
The particles are pulverized into fine particles by secondary collision with the side surface 8a. That is, the material to be pulverized is a fine powder in the order of microns, and this fine powder Tp is supplied from the pulverizing chamber 8 through the passage 9 to the passage 2.
Is sent to the classification process chamber 3 together with the material to be ground Ta. Of the crushed material Ta and the fine powder Tp sent to the classification process chamber 3, the latter fine powder is collected as a product in the direction of the arrow, and the former crushed material and coarse particles are again passed through the passage 4 through the jet jet flow path 5. And crushed by the collision plate 7.

[0005] As described above, the object to be crushed is crushed. However, since the crushing is performed by colliding the object to be crushed with the collision plate, this type of supersonic jet crusher is of the collision type. It is called a supersonic jet crusher. In this apparatus, the fine powder is classified and sorted to 100 μm or less by the above-described manufacturing process, and is supplied for use. In this case, the fine powder is supplied in accordance with the required quality, for example, the particle diameter and the yield value of the fine particles. It is known that the volume, grinding air pressure, grinding air flow rate and the shape of the impingement plate influence.
The impingement plate is disposed in a direction orthogonal to the direction of the jet flow, but has a conical grinding surface protruding at the center and an annular shape formed on an outer peripheral portion connected to the conical grinding surface. A structure having a flat crushed surface (hereinafter sometimes simply referred to as a conical impact plate) is the most excellent, and a sharp particle size distribution can be obtained by the impact plate having the structure.

On the other hand, conventional pulverizers can be roughly classified by pulverization means, such as pulverization by impact (for example, hammer mill, emperor breaker, etc.), pulverization by grinding, and compression (for example, roller mill,
Pulverization by compression (eg, jaw crusher, gyre crusher, etc.), pulverization by impact and shear (eg, ball mill, rod mill, etc.), pulverization by impact and shear (eg, jet mill,
Jetmizer, etc.) are known.

However, the selective use of these pulverizers is governed by the pulverizing capacity (processing capacity for obtaining fine particles having a constant particle size distribution), pulverization efficiency, and the thermal characteristics of the material to be pulverized. In particular, for objects to be crushed such as resin powder or toner mainly composed of a thermoplastic resin, for example, heat generation and temperature rise associated with a sharp increase in energy on the crushing surface during crushing are caused by a conical tip. Crushing by means such as impact, grinding, and compression because the crushed particles are generated and agglomerated and adhered to each other as a result, and fusion to the crushed surface or the contacting portion occurs. The device cannot be used. Therefore, for such materials to be crushed, a large amount of cooling compressed gas or low-temperature gas having a large cooling effect can be used in combination as a crushing medium, so that crushing devices using impact and shear, such as jet mills and jet mizers, can be used. The use of a collision type supersonic jet mill is preferred.

Further, there is still a strong demand for obtaining thermoplastic fine particles at a low cost by highly efficient pulverization.
It is considered to be an advantageous method to realize it by a collision type supersonic jet pulverizer.

[0009]

However, in the collision type supersonic jet pulverizer, when the above-mentioned conical collision plate is used, the pulverized material maintains its speed due to the conander effect of the pulverized surface on the cone. After evenly colliding with a flat portion on an annular shape formed on the outer peripheral portion connected along the slope, the direction is suddenly changed perpendicular to the jet nozzle along the flat surface.
Therefore, while the collision plate having this shape provides the highest pulverization efficiency, the flat portion thereof is severely worn, and there is a problem that the entire collision plate has to be frequently replaced in order to maintain a high throughput.

[0010] Accordingly, the present invention has been made based on the above-mentioned technical background, and an improvement in the durability of the collision plate has been achieved.
It is an object of the present invention to provide a collision type supersonic jet pulverizer in which the problems of improvement of collision plate maintenance and prevention of agglomeration and adhered matter due to heat generated at the tip of a cone are eliminated.

[0011]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that the shape of the crushing surface of the collision plate provided at a position opposed to the jet nozzle of the jet stream has a specific cone shape. A collision type supersonic in which a conical crushing surface having an angle and an annular flat plate crushing surface formed on an outer peripheral portion connected to the conical crushing surface are detachably integrated. The present inventors have found that a jet crushing apparatus is suitable for the above purpose, and have completed the present invention.

That is, according to the present invention, there are provided a nozzle for jetting a jet jet into a pulverizing chamber, a jet jet flow path for supplying an object to be pulverized to the jet jet, and an impingement plate provided at a position facing the jet nozzle. Further comprising a secondary collision plate in which the object to be ground after the primary collision with the collision plate is subjected to a secondary collision with the side surface of the pulverizing chamber, or a collision-type supersonic jet arranged with a dedicated jig. In the crushing device, the shape of the crushing surface of the collision plate is set such that the cone angle θ formed at the center portion with respect to the jetting direction of the jet jet is 3
A conical crushing surface of 0 ° to 150 ° and an annular flat plate crushing surface formed on an outer peripheral portion connected to the conical crushing surface are integrally formed in a detachable form. And a collision type supersonic jet pulverizer is provided.

[0013]

The collision type supersonic jet pulverizer of the present invention has the above-mentioned structure, so that a thermoplastic particle having a sharp particle size distribution with a high pulverization efficiency can be obtained by a conical collision plate, Since the impact plate was divided into a conical portion and a flat plate portion of the outer peripheral portion connected thereto, and integrated in a detachable form, the crushing ability could be restored by replacing only the flat plate portion worn by crushing, In addition, since the back surface of the flat plate portion can be used, the cost of the collision plate can be reduced and the life thereof can be extended.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. The feature of the present invention is that, as shown in FIG. 1, the cone 7a protruding from the collision plate 7 has a conical portion having an apex angle θ of 30 ° to 150 ° and an outer peripheral portion connected thereto. That is, the flat plate collision plate 7b is divided so as to be detachable with the dedicated jig 10. Compared with the conventional integrated type, the split type can restore the crushing ability by replacing only the flat plate worn by the crushing, and the flat plate can be used upside down. At the time of mounting, a conventional bonding method is possible by bolt fixing. Other configurations are the same as those of the related art shown in FIG.

In the present invention, the material of the conical crushing surface of the collision plate and the material of the annular flat crushing surface formed on the outer periphery may be the same or different. In other words, there is an advantage that the combination can be freely selected depending on the crushing characteristics of the crushed object. That is, by selecting an appropriate material for each of the conical pulverized surface and the flat plate pulverized surface, generation of a hot melt can be prevented and pulverization efficiency can be improved. For example, the conical portion 7a has a thermal conductivity of 0.1 cal / cm · sec in a 20 ° C. test in order to avoid the influence of heat storage of frictional heat due to collision of the tip.
・ Ceramics above ° C, such as silicon carbide (SiC)
On the other hand, in the flat plate portion 7b, as the wear characteristics due to the collision, the blast wear amount is reduced by the alumina powder injection angle 30 °.
°, pressure 5.5 kg / cm ² , 0.4 in 2 minute injection test
g or less of wear, for example, silicon nitride (S
i ₃ N ₄ ) and silicon carbide (SiC).

In the present invention, the shape of the tip of the divided conical portion of the collision plate can be changed. For example, as shown in FIG. 2, it is highly preferable that the tip of the conical portion 7a has a shape 7c that draws a smooth arc with respect to the conical slope within a range of 80 to 99% of the height H. When the tip is shaped like 7c, it is possible to avoid the effect of one point concentration of heat storage due to frictional heat of the tip of the cone due to collision, and as a result, it is possible to prevent the generation of a hot melt even in the pulverization of a low softened product. It should be noted that the adoption of such a shape can provide the same effect in a conventional integrated conical collision plate.

Further, in the present invention, it is highly preferable that the ratio of the area of the jet outlet of the jet jet flow path to the area of the bottom surface of the conical portion of the conical collision plate is within a specific range. Explaining with reference to FIG. 3, the ratio (5b / 7d) of the ejection port area 5b of the jet injection flow path 5 facing the conical collision plate and the conical bottom surface area 7d of the conical collision plate.
Is very preferably in the range of 1 / 1.5 to 1/3 (claim 2). In this case, the interval between the ejection port 5c and the flat plate crushing surface of the collision plate is 70 to 70 with respect to the cone height H.
In the range of 150%, it is preferable to bring the flat plate crushing surface close to the jet outlet, so that the tip of the cone is particularly inserted into the jet jet channel. With such a configuration, the jet jet flow containing the object to be crushed collides with the conical crushing surface of the collision plate evenly (that is, the conical slope can be fully utilized), and the crushing efficiency can be improved. Can be increased.

In the present invention, the conical crushing surface of the collision plate and the annular flat crushing surface formed on the outer periphery have a function of rotating in a thrust direction with respect to the opposed jet jet flow path. It is very preferable to form (claim 3). That is, as shown in FIG.
Is provided with a rotating function in the thrust direction with respect to the opposed jet jet flow path 5 so that the flat plate portion crushing surface 7 of the collision plate 7 is provided.
e can be uniformly worn, the durability against the abrasion of the collision plate and the maintenance work can be improved, and the number of replacements of the collision plate can be minimized.

Hereinafter, an operation example and a comparative example of the apparatus of the present invention will be described. All parts shown below are based on weight.

Operation Example 1 A mixture of 15 parts of a polyester resin and 85 parts of a styrene / acrylic resin mixed with 5 parts of a phthalocyanine pigment (softening point: 75 ° C.) was melt-kneaded by a hot roll mill and cooled. The powder obtained by coarse pulverization with a jaw crusher was used as a material to be pulverized. In the crusher shown in FIG. 5, the collision plate 7 was changed to the collision plate shown in FIG. 1 and crushing was performed.
In order to obtain the powder, 80 kg of the material to be ground per hour could be supplied, and if the treatment was performed for 1500 hours in this state, the flat plate collision surface was worn and the processing capacity was reduced to 75 kg / hr. Then, when crushed with the flat plate on the back,
The treatment could be continued at 80 kg / hr for 1500 hours.

The pulverizer has a pulverization pressure of 6.0K.
g / cm ² and a maximum consumption air flow rate of 10 m ³ / min were used. The cost of the flat plate collision plate was reduced to 1/5 of that of the integrated type, and the machine stoppage at the time of replacing the back surface of the flat plate required 0.25 hours. Further, as the material of the collision plate, a conventional alumina ceramic is used, the apex angle θ of the cone is 60 °, the ratio of the cone bottom surface area to the flat plate area is 1: 2, and the jet flow path jet port is used. 1: 2 ratio of area to cone bottom area
Was used.

Comparative Example 1 A pulverizing process was performed using the same raw material and pulverizer as in Operation Example 1 except that a conventional integrated type shown in FIG. 5 was used as the collision plate 7. Average particle size 1
In order to obtain 2 μm, 80 kg of material to be ground per hour could be supplied. If processing is performed for 1500 hours in this state, abrasion occurs on the flat plate collision surface, and the processing capacity is 75 kg.
/ Hr, the collision plate was replaced with a new one. In addition, the machine stopped for the replacement operation required 1.50 hours.

Operation Example 2 A mixture of 10 parts of a polyester resin and 90 parts of a styrene / acrylic resin mixed with 4 parts of a phthalocyanine pigment (softening point: 80 ° C.) was melt-kneaded by a hot roll mill, and cooled. The powder obtained by coarse pulverization with a jaw crusher was used as a material to be pulverized. When the crushing process was performed using the same crusher as in Operation Example 1 except that the impact plate was made of silicon carbide for the conical portion and silicon nitride for the flat plate portion, the volume average particle diameter was 11 μm.
In order to obtain 70 kg of material to be crushed per hour can be supplied, and after 3,000 hours of treatment in this state,
Abrasion occurred on the flat part, and the processing capacity was reduced to 65 kg / hr. Then, when this flat plate was made the back side,
A treatment of 70 kg / Hr was completed for 000 hours.

The pulverizer has a pulverizing pressure of 6.0K.
A machine with a maximum air consumption of 10 m ³ / min at g / cm ² was used, and it took 0.25 hours to stop the machine during the backside replacement work.

Comparative Example 2 A pulverizing process was performed using the same raw material and pulverizer as in Operation Example 2 except that a conventional integrated type shown in FIG. 5 was used as the collision plate 7. Average particle size 1
In order to obtain 1 μm, 70 kg of material to be ground per hour could be supplied. However, 25 hours after the start of operation, heat fusion material was generated at the tip of the conical portion of the collision plate, and the machine had to be stopped. When crushing was performed by continuously repeating the restart of cleaning, abrasion occurred on the flat plate portion for a total of 700 hours.
Alumina was used as the material of the conventional collision plate.

Driving Example 3 A low-softening product having a softening point of 65 ° C. obtained by mixing 3 parts of a phthalocyanine pigment with 12 parts of a polyester resin and 88 parts of a styrene / acrylic resin was melt-kneaded by a hot roll mill. After cooling, the powder obtained by coarse pulverization with a jaw crusher was used as a material to be pulverized. As a collision plate, the conical tip 7c as shown in FIG.
Driving example 1 except that a shape having a smooth arc drawn on the hypotenuse was used so that 95% of the
When a pulverizing treatment was carried out using the same pulverizer as described above, a volume average particle size of 12.5 μm was obtained at 45 hours / hour.
A processing capacity of kg / hr could be obtained.

The pulverizer used had a pulverization pressure of 6.0K.
g / cm ² , the maximum consumption air flow rate was 5 m ³ / min, and the material of the collision plate was alumina.

Comparative Example 3 The same raw material and pulverizer as in Operation Example 1 were used as the collision plate 7 except that the conventional integrated type shown in FIG. 5 was used, and the volume average particle diameter was 12.5 μm. To get
An attempt was made to obtain a pulverized material of 45 kg per hour, but a heat-fused material was generated at the tip of the conical portion of the collision plate, so that pulverization was impossible.

Driving example 4 Jet jet flow path outlet area 5b and impact plate cone bottom area 7
Except for the fact that the ratio to d was 1: 2.5, the same raw material as in Example 1 was subjected to pulverization using a collision plate and a pulverizer. , 1
A processing capacity of 85 kg / hr could be obtained per hour, and when processing was performed for 1500 hours in this state, abrasion occurred on the flat plate collision surface, and the processing capacity was reduced to 80 kg / hr. Then, when this plate was pulverized with the back side, the treatment could be performed at 85 kg / hr for an additional 1500 hours.

Operation Example 5 When the same raw materials, collision plate and pulverizer as in Example 1 were used, and pulverization was performed while further rotating the collision plate, a volume average particle diameter of 12 μm was obtained.
g of the material to be ground could be supplied, and the treatment at 80 kg / hr could be performed for 2500 hours only by using the flat plate surface of the collision plate.

Table 1 summarizes the results of the above operation examples and comparative examples.

[Table 1]

[0032]

According to the first aspect of the present invention, there is provided a collision type supersonic jet crushing apparatus comprising: a jet nozzle for jet jet; a jet jet flow path for supplying an object to be crushed to the jet jet; and a collision plate provided at a position facing the jet nozzle. In the apparatus further comprising a secondary collision plate around which the object to be ground after the primary collision with the collision plate is subjected to a secondary collision, the crushing surface shape of the collision plate with respect to the ejection direction of the jet jet The conical crushing surface having a cone angle θ of 30 ° to 150 ° protruding from the center and the annular flat crushing surface formed on the outer peripheral portion connected to the conical crushing surface are detachable. Because it is constituted by an integrated form in the form, it is possible to obtain thermoplastic particles of sharp particle size distribution with high grinding efficiency by the conical collision plate, and only the flat plate portion of the collision plate worn by grinding To exchange Ri can recover crushing capability, and since the back surface using the flat plate portion is also made possible, it is possible to realize the cost reduction and life extension of the impingement plate.
Further, regarding the material of the conical grinding surface and the flat grinding surface,
Depending on the crushing characteristics of the material to be crushed, the combination can be freely selected and the shape of the tip of the cone can easily be changed, so that generation of heat-fused material can be prevented and crushing efficiency can be improved.

In the collision type supersonic jet pulverizer according to the second aspect, the ratio of the area of the jet port of the jet jet channel to the area of the bottom surface of the conical portion of the conical collision plate is 1 / 1.5 to 1/3. The jet jet flow containing the pulverized material collides with the conical pulverization surface of the collision plate without exception, and it is possible to further improve the pulverization efficiency.

According to a third aspect of the present invention, in the collision type supersonic jet pulverizer, the conical pulverization surface of the collision plate and the annular flat plate pulverization surface formed on the outer periphery are arranged in the thrust direction with respect to the opposed jet jet flow path. With the configuration having the function of rotating, the collision surface of the flat plate portion of the collision plate can be uniformly worn, the durability against the wear of the collision plate and the maintenance work are further improved, and the number of times of replacement of the collision plate is improved. Can be minimized.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a split collision plate used in the present invention.

FIG. 2 is a schematic view showing a modified example of a tip shape of a conical portion of a collision plate used in the present invention.

FIG. 3 is a schematic diagram for explaining the ratio of the area of the bottom surface of the conical portion of the collision plate used in the present invention to the area of the jet outlet of the jet flow path.

FIG. 4 is a schematic view showing an example of a rotary collision plate used in the present invention.

FIG. 5 is a schematic view showing an example of a conventional collision type supersonic jet pulverizer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw material input side 2 Passage 3 Classification process room 4 Passage 5 Jet injection flow path 5a Supply port of crushed material to jet injection flow path 5b Jet injection flow path area 5c Jet injection flow path injection port 6 High pressure air injection nozzle 7 Collision plate 7a Cone of collision plate 7b Flat plate of collision plate 7c Shape of tip of cone of collision plate 7d Bottom area of cone of collision plate 7e Crushing surface of flat plate of collision plate 8 Crushing chamber 8a Side surface of crushing chamber 9 Passage 10 Dedicated Jig Ta Coarsely crushed object Tb Finely crushed object

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toshiyuki Fukase 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (56) References JP-A-2-68155 (JP, A) JP-A Heihei 3-2996447 (JP, A) Japanese Utility Model 3-19543 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B02C 19/00 B02C 19/06

Claims (3)

(57) [Claims] At least a nozzle for jetting a jet jet into a pulverizing chamber, a jet jet flow path for supplying an object to be pulverized to the jet jet, and an impingement plate provided at a position facing the jet nozzle, further comprising: In the collision type supersonic jet pulverizing apparatus, which is provided with a secondary collision plate in which the object to be pulverized after the primary collision with the collision plate is secondarily collided with the side surface of the pulverizing chamber or arranged with a dedicated jig, The crushing surface of the plate has a conical crushing surface with a cone angle θ of 30 ° to 150 ° formed at the center with respect to the jetting direction of the jet jet, and an outer periphery connected to the conical crushing surface. A collision type supersonic jet pulverizer characterized in that an annular flat plate pulverization surface formed in a portion is integrated with a detachable form. 2. The jet area of the jet flow path / the conical collision plate so that the jet of the jet flow path facing the front of the conical pulverization surface can collide with the conical pulverization surface without deviation. 2. The collision type supersonic jet pulverizer according to claim 1, wherein the conical bottom surface area ratio = 1 / 1.5 to 1/3. 3. A conical crushing surface of the collision plate and an annular flat crushing surface formed on an outer periphery thereof have a function of rotating in a thrust direction with respect to an opposed jet jet flow path. Item 3. A collision type supersonic jet pulverizer according to item 1 or 2.